Windows/Mac/Linux: Nobody told Mozilla's developers it's a day off. They've just pushed out a fourth beta of Firefox 3.6, with more than 100 fixes from the last beta and more add-on security and compatibility.

There's no reason not to grab this beta if you're a bleeding-edge Firefox fan, as it doesn't seem to remove any features or support (as its predecessor did), and Mozilla notes that more than 70 percent of its add-ons are now compatible with the 3.6 betas.